Coupling



Juy' 25, i933. M. HoFMANN 1,919,654

COUPLI NG Original Filed Dec. l1, 1929 originaleliminationA fuga Decmberz'ii, 192e, sei-lai No. 413,19'6.

f April 3, 19s1. serial No. 527,593.

Patented July 25, i933.4

'MAXHOFMANN, orwauxnsrre, wrseorfern, .assrenea 'ro yw.autresrre Monroe keoivtu PANYyQF WAUKESHA, WSGQNSIN, A. .CORIPORATQN 0F WSCONSN construe i This invention relates'toan improvement in couplings, and is more particularly directed to a. typo of coupling which" is specially adapted for connecting afiluid conducting tube to afuel pump, injection nozzle,- or like device.

" The coupling comprisingthe present in- Avention may be used for conducting liquid to oiffrom anytype of apparatus, butis of particular value in devices wherein" liquid l1s delivered underpressure.` The preferredt "form of couplingfherein illustrated'and described, vis. shown as connecting afuel tube to the pump chamber of a fuel pump of sim! ilar construction to the pum-p disclosed in my cop'ending application Serial No. 418,196, filed December` 11, 1929, for fuel pump, of vwhich the present applicatin .isa division.

One of the main objectsof lthis invention is to provide means for suitably coupling a tube .with'any form of apparatus such as a pump, injection nozzle, etc.,in such amanner as to avoid necessity of varying the interiorfldiameter of the tube. In maintaimAv ing'a continuous unvarymg)interior` diameter in through the ltube is assured.

Another lobject of the f present invention is 'to provide a coupling, of comparatively Simple and inexpensive construction.

A still f u'rther obj ect is to provide a couplingwhich can lbe adapted "with facility Ato y servev in `its desired capacity to conveniently and quickly 'connect a tube with a device utilizing,v the same, and which will allow removal of the tube 'with' equal ease and eXpefdiency. v'

i Further objects and advantages of my'invention willhereinafter -appfearfrom `the following detailed i description, reference' being had tothe accompanying drawing.

In the drawing Y present invention., illustrating` the same as alfvuel pfurnp, the pump being shown fragmentari'ly and in section; and

Figure 2 isa longitudinalcross sectional viewer a modedform of coupling.

vand interiorly threaded ,at o

,ai tube, a moreV uniform flow of liquid is slightly ared atits upper end for 'this Figure 1 isa longitudinalcross sectional' l n view' through a `coupling comprising the connecting a tube-with the pump chamber of Referring now to ,Figure 1, the coupling` C is here utilized for4 connecting adelivery s tube with a pump for communication with the pump chamber' 3.

In this particular pump construction the pump lblock 1 is vbored tionof as sleeve 6.1 Sleeve 6., providedV at its lower` end with a reduced threadedV neck 7, 'screws intol the upper'end of the opening or'bore above chamber 3an'd a'gaslret 8 is der formedv in the'bloclr about the opening to effect fluid tight and Apressure resistant closure between the `sleeve and the block. Sleeve 6 is interiorly threaded from its lup-l per Aend Vto within ashort distance of `*itsl `lower enchand neck 7 is provided with a reduced bore 9 leading from' the bore of `the sleeve, and with anfoutlet'port' 10 opening Afrom bore 9 into'pump 'chamber Thel lower `end' ofbfore' 9 is tapered-toward port 10 to provide a seat fora ball check valvell nnuda and` uns ,application mea VF for the recep- ,60T interposed rbetween thissleeveand a shoulnormallyheld seated by a spring` l2fc'onfined. i

between 'the ball check valve land the down- "wardly tapering` boss j 13 of la ring 14A` which ts within the lower unthreaded portion of j the bore of sleeveI 6, The opening of this ring islin alignment with boren 9 and the underface of boss 513 is rounded'so as tofseat accurately in the upper end` of borej9, which purpose. j A pressure lring-15, providedwith slots 16'for receptionof elements of va suitable'tool, screws into Asleeve 6 and serves to .secure ring 141 accurately in position when. tubing 17 is being assembled or'v disassembled.

'Ring y15 is provided with 'a central bore of u proper "size tosnugly receive and guidfethe ylower end of thefuel delivery tube 17 f for conducting the fuel underl pressure, fromw ythe pump to any 'suitable point of delivery such as an injection nozzlev of an injection V engine. fThe ring 14;` projects',inwardlybeyond the bore of ring 15, radiallytthereof, so as to extend `beneathithe lower end `of `rtube 17 which seats thereon. i

A .tumble 11e is threaded and brama, or

l otherwise suitably securedfupofn tube 17 and is provided,` at itslower end, Awithan 'outer shoulder p19 slivdable' Within, -k sleeve G. lfheI 25 is provided at its lower end with an out? coupling C.

. coupling.

downwardly and outwardly of the sleeve.

and a clamp nut 20 lits about thimble 18 and screws into the sleeve 6, the surface at the lower end of this nut being inclined downwardly and outwardly of the sleeve for con tact with the inclined shoulder of the thime ble. By turning the nut into the sleeve, tube 17 is forced downwardly so as to seat tightly upon the upper face of ring 14 and form a `liuid tight closure therewith. The thimble and the clamp nut serve to tightly secure the tube in position and also to resist pressure to which the tube is subjected and which might tend to move the tube away from ring 111.. rlhis providessimple and highly eflicient means for securing a tube such as 17 to a pump at the discharge side thereof while avoiding any change in the interior diameter of the tube, which would be apt to affect the flow of vfluid such ,as fuel oil therethrough and, therefore, would tend to interfere with the accuracy of the feed of fuel to the source of use, as to, an injection nozzle of an engine.

Figure 2 illustrates a modified form of In this construction member 21, forming a portion of a device to which tube 17 is connected, is suitably bored out at 22 and threaded as at 22a to. receive the A centrally disposed tapered bore 23 connects the coupling receiving bore with a communicating passage 24. The coupling C is constructed similarly to the preferred form of coupling illustrated in Figure 1 and comprises a thimble 25 threaded. 'and brazed, or otherwise suitably secured upon tube 17 a, and a clamp nut 26. Thimble wardly extending peripheral shoulder 27 slidable within bore 22, the upper face of this shoulder being inclined downwardly and outwardly to receive the lower end of nut 26, the latter being provided with a complementary cooperating surface for snugly engaging shoulder 27. In this construction, tube 17a projects beyond the bottom face of thimble 25, and is provided with a tapered end 28. The inclination of the tapered end 28 of tube 1760 is such that it conforms to the tapered wall of opening 23. When clamp nut 26 is screwed into bore 22, the tapered end 28 of tube 17a is forced tightly into the tapered opening 23 to folrin a fluid tight closure between member 21 and tube 17a.

In both forms of couplings illustrated in' beveled surfaces of the thimble shoulder 19 and the clamp nut 2O are also firmly pressed together when the nut is turned tight to form a second fluid tight seal or closure eX- ternally of thetube and between the tube and sleeve. With the modified form of construction, the same result is obtained. In the latter, one fluid tight seal or closure is effected between the tapered end of tube 17 a and the tapered wall of opening 23, while a second fluid tight seal or closure is effected between the complementary coacting surfaces formed on the bottom face of nut 26 and upper face of shoulder 27, respectively.

While my invention is particularly adapted for use with injection nozzlesand fuel pumps of injection engines, it is also well suited for many other purposes. I do not, therefore, limit my invention to any one particular use.

My invention is not to be strictly limited to the constructions disclosed except so far as itmay be 4so limited by the appended claims.

What I claim is: v

1. In combination in a coupling, al sleeve provided throughI its innerend with a reduced port, an inner ring loose in the sleeve and provided at its outer face with a rounded boss seating in the inner end of the port, the inner face yof the ring being flat, an outer guide ring secured in the sleeve adjacent the inner ring, said inner ring having an opening therethrough communicating with the port and the guide ring having an opening therethrough concentric with the opening ofthe inner ring, a tube slidable through the guide ring and having its inner end seating flat against the inner face of thev inner ring about the opening thereof, and means for securing the tube in the sleeve and for holding the inner end of the tube seated tightly against the outer face of the inner ring.

2. In combination in a coupling, a sleeve provided through its inner end with a reduced port having its outer end flared to form a. seat, an inner ring loose in the sleeve and provided at its outer face withr a.l

rounded boss seating in the flared inner end of the port, the ring having an opening therethrough aligned with the port and the inner face of the ring being flat, an outer guidering secured in the sleeve and having an opening concentric with the opening of the inner ring, a tube slidable through the guide ring and having its inner end seating flat against the inner face of the inner ring about the opening thereof, and means forv securing the tube in the sleeve and for holding the inner end of the tube seated tightly against the outer face of the inner ring..

3. In combination in a coupling, a sleeve provided through its inner end with a reduced port having its outer end arecl to form ay seat, an inner ring loose in the sleeve and providedat its outer face with a. tz'lpered boss seating in the inner end of the port, the

inner face of the ringbeing flat, an outer securing the tube in the sleeve rnd for hold-v ing the inner end of the tube seated tightly against the outer face ofthe inner ring.v l 4. In combination in n coupling, an interiorly threaded sleeve provided through its inner 'end With a concentric reduced port, en

inner ring loose in the sleeve and provided at its outer face with a vrounded boss seating intheinner end of the port, the inner end of the port being shaped tovprovide a sea-t for the boss and said inner ring having a concentric opening therethrough, the inner face of the inner ring being flat, an outer guide ring screwed into the sleeve and having an opening concentric with the opening of the inner ring, a tube slidable through the guide ring and having its yinner end seating flat egeinst the inner face of the inner ring` about the opening thereof, a meinbersecured to the tube and providing an outwardly pro- Ajeoting shoulder therefor, and a clamp nutl screwing into the sleeve and bearing against said shoulder..

Miur HOFMANN. 

